Dev.dynamic configuration

.github/workflows/test.yml

@@ -5,7 +5,7 @@ jobs:
     name: Test
     strategy:
       matrix:
-        platform: [macos-latest, windows-latest]
+        platform: [macos-latest, windows-2019]
     runs-on: ${{ matrix.platform }}
     steps:
     - name: Set up Go 1.17

CHANGELOG.md

@@ -9,10 +9,14 @@
 
 - [ENHANCEMENT] Upgrade to loki v2.4.2. The following metrics will now be prefixed with `agent_dskit_` instead of `cortex_`: `cortex_kv_request_duration_seconds`, `cortex_member_consul_heartbeats_total`, `cortex_member_ring_tokens_owned`, `cortex_member_ring_tokens_to_own`, `cortex_ring_member_ownership_percent`, `cortex_ring_members`, `cortex_ring_oldest_member_timestamp`, `cortex_ring_tokens_owned`, `cortex_ring_tokens_total`. (@rlankfo)
 
+- [ENHANCEMENT] Introduce EXPERIMENTAL support for dynamic configuration. (@mattdurham)
+
 - [FEATURE] Added config read API support to GrafanaAgent Custom Resource Definition.
 
 - [FEATURE] Added consulagent_sd to target discovery. (@chuckyz)
 
+- [BUGFIX] Ensure singleton integrations are honored in v2 integrations (@mattdurham)
+
 # v0.23.0 (2022-01-13)
 
 - [ENHANCEMENT] Go 1.17 is now used for all builds of the Agent. (@tpaschalis)

cmd/agentctl/main.go

@@ -10,6 +10,8 @@ import (
 	"strings"
 	"time"
 
+	"gopkg.in/yaml.v2"
+
 	// Adds version information
 	_ "github.com/grafana/agent/pkg/build"
 	"github.com/grafana/agent/pkg/client/grafanacloud"
@@ -60,6 +62,7 @@ func main() {
 		samplesCmd(),
 		operatorDetachCmd(),
 		cloudConfigCmd(),
+		templateDryRunCmd(),
 	)
 
 	_ = cmd.Execute()
@@ -474,6 +477,40 @@ config that may be used with this agent.`,
 	return cmd
 }
 
+func templateDryRunCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "template-parse [directory]",
+		Short: "dry run dynamic configuration",
+		Long:  `This will load the dynamic configuration, load configs, run templates and then output the full config as yaml`,
+		Args:  cobra.ExactArgs(1),
+
+		RunE: func(_ *cobra.Command, args []string) error {
+			cmf, err := config.NewDynamicLoader()
+			if err != nil {
+				return err
+			}
+			c := &config.Config{}
+			err = cmf.LoadConfigByPath(args[0])
+			if err != nil {
+				return err
+			}
+			err = cmf.ProcessConfigs(c)
+			if err != nil {
+				return fmt.Errorf("error processing config templates %s", err)
+			}
+
+			outBytes, err := yaml.Marshal(c)
+			if err != nil {
+				return err
+			}
+			fmt.Println(string(outBytes))
+			return nil
+		},
+	}
+
+	return cmd
+}
+
 func must(err error) {
 	if err != nil {
 		panic(err)

docs/user/configuration/dynamic-config.md

@@ -0,0 +1,127 @@
+# Dynamic Configuration - Experimental
+
+**This is experimental and subject to change at anytime, feedback is much appreciated. This is a feature that MAY NOT make it production.**
+
+Dynamic Configuration is the combination of two things:
+
+* Loading from multiple files
+* Using templates and datasources
+
+Both of these make heavy use of the excellent [gomplate](https://github.com/hairyhenderson/gomplate). The goal is
+that as the configuration grows that it can be split it up into smaller segments to allow better readability and handling.
+The configurations cannot be patched in any order and instead are allowed at several levels.
+
+The second goal is to allow the use of templating, functions for [gomplate doc](https://docs.gomplate.ca/) go into detail
+on what functions are available.
+
+## Configuration
+
+Location of the dynamic configuration is used via the feature flag `dynamic-config`, then it will use `-config.dynamic-config-path` to
+load the configuration for dynamic configuration.
+
+```yaml
+# Sources to pull template values 
+datasources: 
+  [- <sources_config>]
+
+# Locations to use searching for templates, the system does NOT look into subdirectories. Follows gomplate schema
+# from [gomplate datasources](https://docs.gomplate.ca/datasources/). File and S3/GCP templates are currently supported
+template_paths: 
+  [ - string ]
+
+# Filters allow you to override the default naming convention
+
+agent_filter:            string # defaults to agent-*.yml
+server_filter:           string # defaults to server-*.yml
+metrics_filter:          string # defaults to metrics-*.yml
+metrics_instance_filter: string # defaults to metrics_instances-*.yml
+integrations_filter:     string # defaults to integrations-*.yml
+logs_filter:             string # defaults to logs-*.yml
+traces_filter:           string # defaults to traces-*.yml
+``` 
+
+### sources_config
+```yaml
+# Name of the source to use when templating
+name: string
+
+# Path to datasource using schema from [gomplate datasources](https://docs.gomplate.ca/datasources/) 
+url: string
+
+```
+
+## Templates
+
+Note when adding a template you MUST NOT add the type as the top level yaml field. For instance if using traces:
+
+Incorrect
+
+```yaml
+traces:
+  configs:
+  - name: default
+    automatic_logging:
+      backend: loki
+      loki_name: default
+      spans: true
+```
+
+Correct
+
+```yaml
+configs:
+- name: default
+  automatic_logging:
+    backend: loki
+    loki_name: default
+    spans: true
+```
+
+Configurations are loaded in the order as they are listed below.
+
+### Agent
+
+
+Agent template is the standard agent configuration file in its entirety. The default filter is `agent-*.yml`. Only
+one file is supported. This is processed first then any subsequent configurations found REPLACE the values here, it is
+not additive.
+
+Reference {{< relref "./" >}})
+
+### Server
+
+The default filter is `server-*.yml`, only ONE server file is supported.
+
+Reference {{< relref "./server-config.md" >}})
+
+
+### Metrics
+
+The default filter is `metrics-*.yml`, only ONE metrics file is supported.
+
+Reference {{< relref "./metrics-config.md" >}})
+
+### Metric Instances
+
+The default filter is `metrics_instances-*.yml`. Any metric instances are appended to the instances defined in Metrics above. Any number of metric instance files are supporter.
+
+Reference {{< relref "./metrics-config.md#metrics_instance_config" >}}) in the metrics instance
+
+
+### Integrations
+
+The default filter is `integrations-*.yml`, these support more than one file, and multiple integrations can be defined in a file. Do not assume any order of loading for integrations. For any integration that is a singleton, loading multiple of those will result in an error. 
+
+Reference {{< relref "./integrations/" >}})
+
+### Traces
+
+The default filter is `traces-*.yml`. This supports ONE file.
+
+Reference {{< relref "./traces-config.md" >}})
+
+### Logs
+
+The default filter is `logs-*.yml`. This supports ONE file.
+
+Reference {{< relref "./logs-config.md" >}})

docs/user/cookbook/dynamic-configuration/01_Basics/01_Structure.md

@@ -0,0 +1,64 @@
+# 01 Structure
+
+Dynamic Configuration uses a series of files to load templates. This example will show how they all combine together. Running the below command will combine all the templates into the final.yml. Any failure while loading the config will revert to the original config, or if this is the initial load Grafana Agent will quit. 
+
+`docker run -v ${PWD}/:/etc/grafana grafana/agentctl:latest template-parse file:///etc/grafana/01_config.yml`
+
+## Dynamic Configuration
+
+[config.yml](01_config.yml)
+
+```yaml
+template_paths:
+  - "file:///etc/grafana/01_assets"
+```
+
+Tells the Grafana Agent where to load files from. It is important to note that dynamic configuration does NOT traverse directories. It will look at the directory specified only, if you need more directories then add them to the `template_paths` array. NOTE, if no protocol specified ie `file://` above, then file access will be assumed. `file:///etc/grafana/01_assets` is equivalent to `//etc/grafana/01_assets`
+
+## Agent
+
+Dynamic Configuration will find the first file matching pattern `agent-*.yml` and load that as the base. You can only have one agent template. If multiple matching templates are found then the configuration will fail to load. 
+
+[agent-1.yml](01_assets/agent-1.yml)
+
+```yaml
+server:
+  http_listen_port: 12345
+  log_level: debug
+metrics:
+  wal_directory: /tmp/grafana-agent-normal
+  global:
+    scrape_interval: 60s
+    remote_write:
+      - url: https://prometheus-us-central1.grafana.net/api/prom/push
+        basic_auth:
+          username: 12345
+          password: secretpassword
+integrations:
+  node_exporter:
+    enabled: true
+  agent:
+    enabled: true
+```
+
+## Server
+
+Dynamic configuration will find the first file matching pattern `server-*.yml` and replace the `Server` config block in
+the Agent Configuration. Note that you do NOT include the `server:` tag, dynamic configuration knows by the name that it
+is a configuration block.
+
+You can only have 1 server template.
+
+[server-1.yml](01_assets/server-1.yml)
+
+
+```yaml
+http_listen_port: 12345
+log_level: info
+```
+
+## Final
+
+[final.yml](01_assets/final.yml)
+
+In the above example the `log_level: debug` block will be replaced with `log_level: info` from the server-1.yml

docs/user/cookbook/dynamic-configuration/01_Basics/01_assets/agent-1.yml

@@ -0,0 +1,19 @@
+server:
+  http_listen_port: 12345
+  log_level: debug
+metrics:
+  wal_directory: /tmp/grafana-agent-normal
+  global:
+    scrape_interval: 60s
+    remote_write:
+      - url: https://prometheus-us-central1.grafana.net/api/prom/push
+        basic_auth:
+          username: 12345
+          password: secretpassword
+integrations:
+  node_exporter:
+    autoscrape:
+      enable: true
+  agent:
+    autoscrape:
+      enable: true